Bruce Hartpence - Packet Guide to Core Network Protocols

Copyright 2011 Bruce Hartpence

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For those not familiar with OReilly books, they commonly do two things: provide lots of solid information and help with the real world. Ive tried to do the same thing here. So this book is terrific for anyone trying to understand networks for the first time and anyone who works with them on a regular basis.

If you have never run packet capture or analysis software, the first time is always an eye opener. All those packets whizzing around the network and each one chock full of arcane information. With this book as a guide you will be able to interpret what is seen and understand why it is there.

For the professional out there, well, we forget things and sometimes get lost in the weeds. When that happens or if you need a refresher, this book is a great reference, not only for the chapter content but for the decomposition of the standards as well. The expert in the field will also find many details not explained elsewhere.

Many networking texts start with models, but this is models with a twist. This book focuses on the TCP/IP model, and this chapter gives them a place in the universe and describes where the focus should be. Backed up with captures and standards, the models are populated with protocols, equipment, and addresses.

Ethernet provides the basis for a very large percentage of the networks deployed today. This chapter discusses the choices of the network administrator while providing significant details about operation and configuration. Topologies and cabling are two other focal points providing further details into actual networking practice.

Leaving Layer 2, we arrive at Layer 3 and the domain of IP. This chapter takes us through the structure and operation of IP, backed up by packet captures of course. Every field is given an example. Particular attention is paid to the addressing and how it is deployed, including the entries standard to the host routing table.

ARP is arguably the simplest protocol on a network, but it is also a very neat trouble shooting tool and a point of attack for the bad guys. This chapter discusses the operation and particular addressing associated with ARP. It also covers storage of learned information and network behavior.

It is easy to outline network device responsibilities and assign them to the various layers of the networking model. This chapter goes a step further to include tables used in making forwarding decisions and guides the reader through a series of step-by-step examples.

This protocol defines a large collection of error and informational message types. However, contemporary networks utilize a subset of this collection. For every one of these practical messages types, a topology is provided and sample packet captures analyzed to give the reader a complete understanding of the situations resulting in their transmission.

A network cannot be built without using network masks. This chapter describes the subnetting and supernetting procedures and provides two methods for arriving at the correct answer when dividing up address space. Several examples are provided and explained completely.